Solid state emitter package including red and blue emitters

ABSTRACT

A solid state emitter package includes a principally red solid state emitter having peak emissions within 590 nm to 680 nm, a principally blue solid state emitter having peak emissions within 400 nm to 480 nm, and at least one of a common leadframe, common substrate, and common reflector, with the package being devoid of any principally green solid state emitters having peak emissions between 510 nm and 575 nm. A solid state emitter package may include at least one electrically conductive path associated with the solid state emitter package that is not in electrical communication with any solid state emitter of the solid state emitter package, with such electrically conductive path being susceptible to inclusion of a jumper or a control element.

FIELD OF THE INVENTION

The present invention relates to solid state light emitters, includingpackages for solid state light emitters and devices incorporating same.

DESCRIPTION OF THE RELATED ART

Color reproduction is typically measured using the Color Rendering Index(CRI Ra). CRI Ra is a modified average of the relative measurements ofhow the color rendition of an illumination system compares to that of areference radiator when illuminating eight reference colors, i.e., it isa relative measure of the shift in surface color of an object when litby a particular lamp. The CRI Ra equals 100 if the color coordinates ofa set of test colors being illuminated by the illumination system arethe same as the coordinates of the same test colors being irradiated bythe reference radiator. Daylight has a high CRI (Ra of approximately100), with incandescent bulbs also being relatively close (Ra greaterthan 95), and fluorescent lighting being less accurate (typical Ra of70-80).

Solid state light sources may be utilized to provide colored (e.g.,non-white) or white LED light (e.g., perceived as being white ornear-white), as has been investigated as potential replacements forwhite incandescent lamps. A solid state lighting device may include, forexample, at least one organic or inorganic light emitting diode (“LED”)or a laser. A representative example of a white LED lamp includes apackage of a blue LED chip, made of InGaN and/or GaN, coated with aphosphor (typically YAGrCe or BOSE). Blue LEDs made from InGaN exhibithigh efficiency (e.g., external quantum efficiency as high as 60%). In ablue LED/yellow phosphor lamp, the blue LED chip produces an emissionwith a wavelength of about 450 nm, and the phosphor produces yellowfluorescence with a peak wavelength of about 550 nm upon receipt of theblue emission. Part of the blue ray emitted from the blue LED chippasses through the phosphor, while another portion of the blue ray isabsorbed by the phosphor, which becomes excited and emits a yellow ray.The viewer perceives an emitted mixture of blue and yellow light aswhite light. A blue LED and yellow phosphor device typically goodefficacy but only medium CRI Ra (e.g., between 70 and 80), or very goodCRI Ra and low efficacy.

Various methods exist to enhance cool white light to increase itswarmth. To promote warm white colors, an orange phosphor or a mix of redand yellow phosphor can be used. Cool white emissions from a whiteemitter may also be supplemented with red and/or cyan LEDs, such asdisclosed by U.S. Pat. No. 7,095,056 (Vitta) to provide warmer light.

As an alternative to stimulating a yellow phosphor with a blue LED,another method for generating white emissions involves combined use ofred, green, and blue (“RBG”) light emitting diodes in a single package.The combined spectral output of the red, green, and blue emitters may beperceived by a user as white light. Each “pure color” red, green, andblue diode typically has a full-width half-maximum (FWHM) wavelengthrange of from about 15 nm to about 30 nm. Due to the narrow FWHM valuesof these LEDs (particularly the green and red LEDs), light made fromcombinations of red, green, and blue LEDs may exhibit low efficacy ingeneral illumination applications.

Another example of a known white LED lamp includes a package includingultraviolet (UV) based LEDs combined with red, green, and bluephosphors. Such lamps provide acceptably high color rendering, butexhibit low efficacy due to Stokes losses.

It is known to mount solid state light sources, such as semiconductorlight emitting devices in packages that may provide protection, colorenhancement, focusing, and similar utilities for light emitted by alight emitting device. Examples of such packages are disclosed in U.S.Patent Application Publication Nos. 2005/0269587, 2004/0126913, and2004/0079957.

Output efficiency and thermal management present ongoing concerns withknown solid state emitter devices. Certain end uses such as grow lightsto promote photosynthesis obtain limited benefit from solid state lightsources intended for illumination pleasing to a human viewer. Solidstate emitter packages as described in the above-referenced publicationsmay be suitable for high power, solid state illumination applications;however, factors such as controllability, output efficiency, thermalmanagement, and manufacturability present ongoing concerns. Thereremains a need for improved packages each including multiple LEDs (e.g.,with features to enhance or tailor light output quality, efficiency,thermal properties, and/or controllability for a desired end use), and aneed for improved devices incorporating such packages.

SUMMARY OF THE INVENTION

The present invention relates to solid state light emitters, includingpackages for solid state light emitters and devices incorporating same.

In one aspect, the present invention relates to a solid state emitterpackage including a plurality of solid state emitters consisting of atleast one principally red solid state emitter having peak emissionswithin a wavelength range of from 590 nm to 680 nm, and at least oneprincipally blue solid state emitter having peak emissions within awavelength range of from 400 nm to 480 nm, wherein the solid stateemitter package is devoid of any principally green solid state emittershaving peak emissions within a wavelength range of between 510 nm and575 nm. The solid state emitter package includes at least one of thefollowing elements (a) to (c): (a) a common leadframe including aplurality of conductive leads arranged to supply current to theplurality of solid state emitters; (b) a common substrate arranged tostructurally support the plurality of solid state emitters; and (c) acommon reflector arranged to reflect light emissions of each solid stateemitter of the plurality of solid state emitters.

In another aspect, the invention relates to a solid state emitterpackage including a plurality of solid state emitters including: (i) atleast one principally red solid state emitter having peak emissionswithin a wavelength range of from 590 nm to 680 nm, (ii) at least oneprincipally blue solid state emitter having peak emissions within awavelength range of from 400 nm to 480 nm, and (iii) at least onesupplemental solid state emitter having peak emissions within awavelength range of from 480 nm to below 510 nm or a wavelength range offrom above 575 nm to 590 nm. The solid state emitter package is devoidof any principally green solid state emitter having peak emissionswithin a wavelength range of between 510 nm and 575 nm, and the solidstate emitter package includes at least one of the following elements(a) to (c): (a) a common leadframe including a plurality of conductiveleads arranged to supply current to the plurality of solid stateemitters; (b) a common substrate arranged to structurally support theplurality of solid state emitters; and (c) a common reflector arrangedto reflect light emissions of each solid state emitter of the pluralityof solid state emitters.

In another aspect, the invention relates to a solid state emitterpackage including: a plurality of solid state emitters; a plurality ofconductive leads in electrical communication with the plurality of solidstate emitters; and at least two spatially separated conductive leads inelectrical communication with at least one electrically conductive pathassociated with the solid state emitter package, wherein the at leastone electrically conductive path is not in electrically conductivecommunication with any solid state emitter of the solid state emitterpackage.

In another aspect, the invention relates to a solid state emitterpackage including a plurality of solid state emitters, a plurality offirst conductive leads in electrical communication with the plurality ofsolid state emitters; and at least two second conductive leads inelectrical communication and disposed on different sides of the solidstate emitter package, wherein the at least two second conductive leadsare not in electrically conductive communication with any solid stateemitter of the plurality of solid state emitters.

Other aspects, features and embodiments of the invention will be morefully apparent from the ensuing disclosure and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an upper perspective view of an emitter device packageincluding four solid state emitter diodes arranged in a unitary packageand capable of producing white light.

FIG. 2A is an upper perspective view of an emitter device packagesubstantially similar to the package of FIG. 1, with a lens covering themultiple emitter diodes.

FIG. 2B is an upper perspective view of a portion of the emitter devicepackage of FIG. 2A, showing the package without the lens to expose theemitter diodes and associated structures.

FIG. 2C is a top view of the emitter device package portion of FIG. 2B.

FIG. 2D is a bottom view of the emitter device package of FIGS. 2A-2C.

FIG. 3 is a simplified top view of a portion of a multi-emitter devicepackage, including three emitters and a conductive path independent ofthe emitters arranged to receive a jumper.

FIG. 4 is a simplified top view of at least a portion of a lightingsystem including a multi-emitter device package having three emittersand a conductive path independent of the three emitters, with the systemincluding multiple electrically operable elements external to themulti-emitter device package in electrical communication with theconductive path.

FIG. 5 is a simplified top view of at least a portion of a lightingsystem including a first multi-emitter device package having multipleemitters and a conductive path independent of the three emitters, withat least one control element coupled to the conductive path to affectoperation of at least one of the first multi-emitter device package anda second multi-emitter device package.

FIG. 6 is a CIE diagram illustrating the blackbody locus and a region ofwhite light.

DETAILED DESCRIPTION OF THE INVENTION, AND PREFERRED EMBODIMENTS THEREOF

The present invention now will be described more fully hereinafter withreference to the accompanying drawings, in which embodiments of theinvention are shown. The present invention may, however, be embodied inmany different forms and should not be construed as limited to thespecific embodiments set forth herein. Rather, these embodiments areprovided to convey the scope of the invention to those skilled in theart. In the drawings, the size and relative sizes of layers and regionsmay be exaggerated for clarity.

It will be understood that when an element such as a layer, region orsubstrate is referred to as being “on” or extending “onto” anotherelement, it can be directly on or extend directly onto the other elementor intervening elements may also be present. In contrast, when anelement is referred to as being “directly on” or extending “directlyonto” another element, no intervening elements are present. It will alsobe understood that when an element is referred to as being “connected”or “coupled” to another element, it can be directly connected or coupledto the other element or intervening elements may be present. Incontrast, when an element is referred to as being “directly connected”or “directly coupled” to another element, no intervening elements arepresent.

Unless otherwise defined, terms (including technical and scientificterms) used herein should be construed to have the same meaning ascommonly understood by one of ordinary skill in the art to which thisinvention belongs. It will be further understood that terms used hereinshould be interpreted as having a meaning that is consistent with theirmeaning in the context of this specification and the relevant art, andshould not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein.

As used herein, the terms solid state light emitter or solid state lightemitting device may include a light emitting diode, laser diode and/orother semiconductor device which includes one or more semiconductorlayers, which may include silicon, silicon carbide, gallium nitrideand/or other semiconductor materials, a substrate which may includesapphire, silicon, silicon carbide and/or other microelectronicsubstrates, and one or more contact layers which may include metaland/or other conductive materials.

Solid state light emitting devices according to embodiments of theinvention may include III-V nitride (e.g., gallium nitride) based LEDsor lasers fabricated on a silicon carbide substrate such as thosedevices manufactured and sold by Cree, Inc. of Durham, N.C. Such LEDsand/or lasers may be configured to operate such that light emissionoccurs through the substrate in a so-called “flip chip” orientation.

A solid state emitter as disclosed herein can be saturated ornon-saturated. The term “saturated” as used herein means having a purityof at least 85%, with the term “purity” having a well-known meaning tothose skilled in the art, and procedures for calculating purity beingwell-known to those skilled in the art.

One aspect of the invention relates to use of at least one principallyred solid state emitter and at least one principally blue solid stateemitter in a solid state emitter package that is devoid of anyprincipally green solid state emitter. The at least one principally redemitter and the at least one principally blue solid state emitter eachpreferably comprise at least one LED. The emitter package preferablyincludes at least one, more preferably at least two, and still morepreferably all three, of the following features (a) to (c): (a) a commonleadframe including a plurality of conductive leads arranged to supplycurrent to the solid state emitters; (b) a common substrate arranged tostructurally support the solid state emitters; and (c) a commonreflector arranged to reflect light emissions of each solid stateemitter of the plurality of solid state emitters.

Placing both principally red and principally blue emitters in a singlepackage may enhance color mixing by placing the different color sourcesclose together. Principally blue emitters such as InGaN-based LEDs aredesirably used due to their high efficiency. Principally red emitterssuch as red LEDs are desirably used to enhance warmth and spectral widthof the resulting mixed light. Relative to principally red emitters,principally green emitters such as green LEDs are not as useful toenhance warmth of light sourced from principally blue emitters, andrelative to principally blue emitters, principally green emitters (e.g.,green LEDs) are less efficient. As a result, Applicants have found thatgreen LEDs may be omitted from a solid state emitter package includingat least one principally red solid state emitter and at least oneprincipally blue solid state emitter, without negatively impactingefficiency. Moreover, in certain end uses that do not benefit from greenlight, the omission of a principally green emitter eliminates needlessinclusion of a principally green emitter and attendant wasted energy.For example, green leaves of plants readily absorb red light and bluelight, but reflect green light. No benefit is realized by including aprincipally green solid state emitter in a grow lamp intended to promoteplant growth by emission of an electromagnetic spectrum appropriate forphotosynthesis.

The term “principally red” as applied to a solid state emitter hereinrefers to an emitter having peak emissions within a wavelength range ofpreferably from about 590 nm to about 680 nm, more preferably from about595 to about 675 nm, more preferably from about 600 to about 670 nm, andstill more preferably from about 610 to about 660 nm.

The term “principally blue” as applied to a solid state emitter hereinrefers to an emitter having peak emissions within a wavelength range ofpreferably from about 400 nm to about 480 nm, more preferably from about405 nm to about 475 nm, more preferably from about 410 nm to about 470nm, and still more preferably from about 420 nm to about 460 nm.

The term “principally green” as applied to a solid state emitter hereinrefers to an emitter having peak emissions within a wavelength range ofpreferably from 510 nm to 575 nm, or more preferably between 510 nm and575 nm.

The terms “multi-emitter package” or simply “emitter package” as usedherein refers generally to a light emission device including multiplesolid state emitters in conjunction with at least one of a commonleadframe, a common submount, and a common reflector.

While solid state emitters and lumiphoric materials are recognized tohave relatively narrow wavelength emission ranges (e.g., full width/halfmaximum wavelength spectra of less than about 20 nm in many instances),is to be understood that assignment of individual colors to suchemitters and conversion materials refers to peaks or centers of outputwavelengths. That is, individual emitters and lumiphoric materialstypically have dominant or peak wavelengths where emissions aremaximized, but an individual emitter or lumiphoric material may emit arange of other wavelengths (typically at substantially reduced intensityand efficiency) than its dominant or peak wavelength.

In one embodiment, a solid state emitter package comprises a pluralityof solid state emitters including at least one principally red solidstate emitter, and including at least one principally blue solid stateemitter, may be supplemented with at least one supplemental solid stateemitter having peak emissions within a wavelength range of from 480 nmto below 510 nm (e.g., principally cyan) or a wavelength range of fromabove 575 nm to 590 nm (e.g., principally yellow and/or amber). Theplurality of solid state emitters is also devoid of any principallygreen solid state emitter. The at least one supplemental solid stateemitter serves to reduce spectral gaps in the aggregated spectral outputof the package, while avoiding peak emissions within a principally greenspectrum. The emitter package preferably includes at least one, morepreferably at least two, and still more preferably all three, of thefollowing features (a) to (c): a common leadframe including a pluralityof conductive leads arranged to supply current to the solid stateemitters; (b) a common substrate arranged to structurally support thesolid state emitters; and (c) a common reflector arranged to reflectlight emissions of each solid state emitter of the plurality of solidstate emitters.

Various methods may be used to tailor aggregated emissions of a solidstate emitter package as disclosed herein according a desired end use.In one embodiment, current is independently controllable to each emitterof a plurality of solid state emitters in a solid state emitter package,or, alternatively, to different groups of solid state emitters ofdifferent principal colors. Independent control of current to differentsolid state emitters of different principal colors enables a user toadjust or tune output color, as well as adjust luminous flux. In oneembodiment, at least one current adjuster may be directly or switchablyelectrically connected to each solid state emitter or different groupsof solid state emitters, to adjust current. In one embodiment, one ormore solid state emitters of a plurality of emitters may be deactivatedwhile current is supplied to other solid state emitters to providedesired luminous flux and/or output color. In one embodiment, the numberand/or size of emitters of different principal colors may be adjusted toprovide desired luminous flux and/or output color. In one embodiment,any one or more of the foregoing methods for tailoring aggregatedemissions of a solid state emitter package may be combined foradditional advantage.

In one embodiment, solid state emitters of multiple different principalcolors within a package as described herein may be operatively adjustedor controlled to triangulate to one or more points along or near ablackbody locus drawn on a CIE chromaticity diagram, such as shown inFIG. 6 (with the curved line emanating from the 800 nm cornerrepresenting the blackbody locus). In one embodiment, the preceding oneor more points may be within ten MacAdam ellipses of at least one pointon the blackbody locus on a 1931 CIE Chromaticity Diagram.

In one embodiment, a plurality of solid state emitters includes multipleemitters of the same principal color (i.e., principally red, principallyblue, principally cyan, principally yellow, and/or principally amber),with multiple emitters of the same principal color having peak emissionsof different wavelengths. Such emitters of the same principal color mayhave peak emissions at wavelengths that differ, with such peakwavelengths in some cases differing by preferably at least about 2 nm,more preferably at least about 4 nm, more preferably at least about 8nm, more preferably at least about 15 nm, more preferably at least about30 nm, and still more preferably at least about 40 nm. For example, twoprincipally red LEDs may include a first red emitter having peakemissions at a wavelength of about 640 nm and a second Portland orangeLED having peak emissions at 605 nm (representing a difference of 35 nmrelative to the 640 nm red LED), and two principally blue LEDs mayinclude a first blue LED having peak emissions at a wavelength of about450 nm and a second blue LED having peak emissions at a wavelength ofabout 460 nm. Preferably, current to each emitter is independentlycontrollable. Use of multiple emitters within the same principal colorhaving different peak wavelengths provides enhanced color controlcapability, and enhances spectral width of aggregated emissions.

In certain embodiments, each solid state emitter of a multi-emitterpackage is primarily characterized by output emissions in the visiblerange. Various embodiments of solid state emitter packages as disclosedherein may be devoid of any solid state emitter having peak emissions inthe ultraviolet spectrum.

In certain embodiments, a solid state emitter package as disclosedherein may include at least one luminescent (also called lumiphoric')materials, such as phosphors, scintillators, lumiphoric inks) and/orfilters, arranged to receive light of an input (or stimulation)wavelength range and convert such light to generate emissions (light) ofa different peak wavelength or wavelength range, of any of variousdesired colors—including combinations of colors that may be perceived aswhite. Lumiphoric materials may provide up-converting or down-convertingutility (i.e., outputting higher peak wavelength or lower peakwavelength spectra, respectively). Inclusion of lumiphoric materials insolid state emitter packages may be accomplished by adding suchmaterials to encapsulants, adding such materials to lenses, or by directcoating of such materials onto one or more LEDs. Lumiphoric materialsmay be conformally coated on one or more individual solid stateemitters. In one embodiment, a thicker coating and/or greaterconcentration of lumiphoric material (e.g., relative to a binder) may beapplied to an individual solid state emitter or group of solid stateemitters relative to another solid state emitter or group of emitters.Other materials, such as dispersers, scattering materials, and/or indexmatching materials, may be included in encapsulants, whether or notcombined with lumiphoric materials. Various optical elements, includingbut not limited to collimators, may also be provided in a solid stateemitter package according to embodiments of the present invention.

In one embodiment, at least one lumiphoric material may be remotelylocated (i.e., spatially separated) from a solid state emitter. Remoteplacement of at least one lumiphoric material may be accomplished byseparating a lumiphoric material from a solid state emitter by anintervening material and/or void. A remotely located lumiphoric materialmay be insubstantially thermally coupled with an associated solid stateemitter. Remote placement of a lumiphoric material may be beneficial topromote mixing between emissions of emitters of different principalcolors. In various embodiments, the distance between a solid stateemitter and remotely located phosphor(s) may be preferably about 0.5 mm,more preferably about 1.0 mm, more preferably about 1.5 mm.

Emissions from a solid state emitter having an associated lumiphoricmaterial may be fully absorbed by the lumiphor (for responsiveconversion to another wavelength), or only partially absorbed to enablepassage of a portion of emission from the solid state emitter—such thata solid state emitter and lumiphor in combination may be adapted to emitone color peak or two color peaks (with each color peak preferably beingin the visible range).

One or more lumiphoric materials (e.g., one or more first lumiphor(s)and one or more second lumiphor(s)) may be used in embodiments of thepresent invention. Each of the at least one first lumiphor and the atleast one second lumiphor can individually comprise (or can consistessentially of, or can consist of) a phosphor. Each of the at least onelumiphor can, if desired, further comprise (or consist essentially of,or consist of) one or more highly transmissive (e.g., transparent orsubstantially transparent, or somewhat diffuse) binders, e.g., made ofepoxy, silicone, glass, or any other suitable material. For example, ifa lumiphor comprises one or more binders, then one or more phosphors canbe dispersed within the one or more binders. In general, the thicker thelumiphor, then the lower the weight percentage of the phosphor may be.Depending on the overall thickness of the lumiphor, the weightpercentage of the phosphor could be generally any value, e.g., from 0.1weight percent to 100 weight percent

In one embodiment, at least one lumiphoric material is arranged toreceive and convert emissions from any of (i) at least one principallyred solid state emitter, and/or (ii) at least one principally blue solidstate emitter, wherein the lumiphoric material is adapted to generateemit peak emissions of a wavelength that is different from a peakemission wavelength of each of the at least one principally red solidstate emitter and the at least one principally blue solid state emitter.The degree of difference between the peak wavelength of the at least onelumiphoric material and the peak wavelength of each of the at least oneprincipally red emitter and the at least one principally blue emitter ispreferably at least about 10 nm, more preferably at least about 20 nm,more preferably at least about 30 nm, more preferably at least about 40nm, and still more preferably at least about 50 nm. In one embodiment, aplurality of solid state emitters comprises at least two solid stateemitters having peak emissions of wavelengths at least about 50 nmapart.

In one embodiment, a lumiphoric material is arranged to receive andconvert emissions from any of (i) at least one principally red solidstate emitter, (ii) at least one principally blue solid state emitter,and/or (iii) at least one supplemental solid state emitter (e.g.,principally cyan, principally yellow, and/or principally amber), whereinthe lumiphoric material is adapted to generate peak emissions of awavelength that is different from a peak emission wavelength of each ofthe at least one principally red solid state emitter, the at least oneprincipally blue solid state emitter, and the at least one supplementalsolid state emitter. The degree of difference between the peakwavelength of the at least one lumiphoric material and the peakwavelength of each solid state emitter may be consistent with the priorembodiment. The at least one supplemental solid state emitter may serveto improve CRI Ra for combinations of emitters that would otherwise becharacterized by cooler color temperature output. A solid state emitterpackage according to one embodiment may include one principally redsolid state emitter, two principally blue solid state emitters havingpeak emissions of a wavelength of about 450 nm, and one principally cyansolid state emitter having peak emissions of a wavelength of from about480 nm to about 490 nm.

In one embodiment, a solid state emitter package includes at least oneprincipally red solid state emitter, at least one principally blue solidstate emitter, and at least one lumiphoric material (e.g., a YAGphosphor or other phosphor) adapted in combination to provide a high CRIwarm white color temperature. Multiple phosphors and/or at least onesupplemental solid state emitter may be added to the foregoing packagefor additional advantage.

In one embodiment, a solid state emitter package includes at least oneprincipally red solid state emitter comprising a Portland orange solidstate emitter, and at least one principally blue solid state emitter, toprovide higher efficiency but lower CRI relative to the preceding (e.g.,phosphor-enhanced) embodiment.

Referring now to FIG. 1, a solid state light emitter package 50according to some embodiments of the present invention includes multiple(e.g., four) independently controllable solid state emitters 12A-12Darranged over (i.e., on or adjacent to) a common submount 14 and acommon leadframe 11. While four solid state emitters 12A-12D areillustrated in FIG. 1, it is to be understood that any desirable numberof solid state emitters may be embodied in a single package. The package50 includes a molded package body 10 surrounding or at least partiallyencasing the leadframe 11 and a lens 20 mounted over a central region ofthe package 50. Although the lens 20 is shown as being substantiallyhemispherical in shape, other lens shapes may be used. Conductive traces19 provided on or over the submount 14, and wirebonds 18, provideelectrically conductive paths between the emitters 12A-12D andelectrical leads 15A-15D and 16A-16D extending from sides of the packagebody 10. Double wirebonds 18 may be used as desired to facilitate evendistribution of electrical current and reduce heating of the wires. Theleads 15A-15D, 16A-16D may be arranged such that leads of oppositepolarity type (e.g. anodes or cathodes) are provided on opposite sidesof the package body 10, which may facilitate the connection of packagesusing such leadframes in series. Registration features or moldingdepressions 8A-8D may be provided adjacent to corners of the in thepackage body 10. A peripheral reflector 21 may be provided below thelens 20. Any of various optional features, such as mixers, diffusers,etc., may be provided in addition to or instead of the lens 20.

The package 50 may have length and width dimensions of 7.0 mm×9.0 mm,inclusive of the leads 15A-15D, 16A-16D following crimping/trimmingthereof. Each emitter of the four emitters 12A-12D disposed in theunitary package may be arranged with lateral edge spacing of less thanabout 1.0 mm, more preferably less than about 0.5 mm, from at least oneadjacent emitter. Such close lateral spacing is desirable to approximatea point source, and thereby minimize perception of discrete colorsources when multiple emitters of different colors are operatedsimultaneously—thus promoting color mixing and shadow reduction. Eachsolid state emitter 12A-12D may have a top emissive surface (facial)area of about 1.0 mm². Given the presence of four solid state emitters12A-12D, the ratio of solid state emitter top emissive surface or facialarea to total facial package area (of about 63 mm²) is about 4/63, orabout 6.3%. In an alternative embodiment, one or more emitters may havea top emissive surface (facial) area of at least about 1.4 mm²; assumingthe presence of four such emitters in the same overall facial packagearea (about 64 mm²), the ratio of solid state emitter top emissivesurface or facial area to total facial package area is at least about5.6/63, or at least about 8.9%. Multi-emitter packages with integralleadframes, and optionally including integral ESD devices, in similarembodiments may be characterized by ratios of solid state emitter topsurface (facial) area to total top surface (facial) package area ofpreferably at least about 4%, more preferably at least about 5%, morepreferably at least about 6%, more preferably at least about 7%, morepreferably at least about 8%, more preferably at least about 9%, andstill more preferably at least about 10%. In a multi-emitter package asdescribed herein, at least one or each different color solid stateemitter (e.g., red and blue, optionally supplemented by at least onesupplemental emitter) or different solid state emitter/lumiphorcombination (e.g., blue emitter/yellow phosphor combination) preferablyhas a ratio of solid state emitter top surface area or facial area tooverall package top facial area of at least about 1/63 (or about 1.6%),more preferably at least about 1.4/63 (or about 2.2%). In oneembodiment, such a package is configured with multiple solid stateemitters of different principal colors, including at least onelumiphor-converted solid state emitter (e.g., to produce white light orlight of any suitable color or dominant that may be different from, orsubstantially the same as, emissions of one or more of the other solidstate emitters).

Presence of multiple independently controllable solid state emitters ofdifferent color provides design flexibility for applications requiringcolor changing with high flux from compact lighting sources. Eachemitter of a multi-emitter package as disclosed herein is preferablyclosely spaced to provide enhanced color mixing and shadow reduction fordesired application. In one embodiment, an entertainment light providesspinning color with high luminous flux. In another embodiment, a colorchanging light bulb includes at least one solid state emitter package,and preferably multiple packages, as disclosed herein. Such colorchanging light bulb may be of any suitable type, including, but notlimited to, R16, MR16, MR16A, and MR16B bulb types.

Emitter packages as disclosed herein may be integrated with orassociated with light mixing elements and/or light devices of varioustypes. In one embodiment, spectral content of an emitter package may beshifted by the inclusion of spatially separated lumiphoric material(e.g., lumiphor films), as disclosed in U.S. Patent ApplicationPublication No. 2007/0170447 to Negley, et al., which is incorporated byreference. First and second lumiphors (e.g., lumiphor films, lumiphorcoatings, and/or lumiphor dispersions) are spaced from one another.Preferably, at least one second lumiphor is spaced apart from, andoutside of, at least one first lumiphor relative to at least one solidstate emitter. Such shifting is preferably accomplished to providecombined emission with improved color rendering index. The presence ofspaced-apart lumiphors provides enhanced color mixing, as may bebeneficial for use with an emitter package including plural solid stateemitters arranged to emit different colors, so as to minimize perceptionof simultaneous emission of distinct colors. Solid state emitterpackages (e.g., packages 50, 50′) as described herein may be combinedwith any one or more features as described in the foregoing U.S. PatentApplication Publication No. 2007/0170447 to Negley, et al.

In certain embodiments, emitter packages (e.g., packages 50, 50′) asdescribed herein may be enhanced and/or tuned using light scatteringmaterials that are arranged in configurations that are non-uniformrelative to the emitters as a group, and/or relative to individualemitters, as disclosed by U.S. Patent Application Publication No.2008/0308825 to Chakraborty, et al. As indicated previously, it isdesirable to place emitters of different colors in close proximity toone another to approximate a point source, and thereby minimizeperception of discrete color sources when multiple emitters of differentcolors are operated simultaneously. Emitter packages as disclosed hereinthat include multiple emitters (or emitters and emitter/phosphorcombinations) of different colors (e.g., emitters 12A-12D of FIG. 1) maybe operated in combination to generate light that is perceived at white(or a desired color mix) when a viewer is directly facing the package(e.g., substantially perpendicular to an upper surface of the packagebody 10), but discrete colors of light (rather than white or anotherdesired color mix) might be perceived by a viewer facing the packagefrom the side (e.g., substantially parallel to an upper surface of thepackage body 10) or at an angle. To overcome this effect without undulyreducing light intensity emitted perpendicular to an upper surface ofthe package body 10, one or more scattering elements (e.g., scatteringelements dispersed in encapsulant) may be arranged to interact withlight that would otherwise emanate from the package at a shallow angle,while light emanating from the emitters in a direction perpendicular tothe upper surface of the package body 10 may interact with a reducedconcentration (e.g., low concentration or zero concentration), ordifferent type, of scattering elements.

The individually controllable solid state emitters may be driven withany appropriate level of current. In one embodiment, each emitter isadapted to be driven with a current of up to at least about 700 mA. Invarious embodiments, currents of 350 milliamps, 700 milliamps, or moremay be supplied to each emitter within a solid state emitter package. Invarious embodiment, a light emission package as disclosed herein andincluding multiple emitters of different principal colors has a totallumen output of preferably at least about 300 lumens, more preferably atleast about 350 lumens, and still more preferably at least about 400lumens. In various embodiments, a solid state emitter package asdescribed herein has a CRI of at least about 80. In various embodiments,a solid state emitter package as described herein has an efficacy of atleast about 25 lumens per watt.

With continued reference to FIG. 1, the leadframe 11 preferably comprisea thermally conductive material (e.g., a metal), and preferably definesa heatsink that may or may not be electrically active. The submount 14may comprise a thermally conductive but electrically insulating material(e.g., aluminum nitride, a ceramic, etc.). The submount 14 may beattached to the leadframe 11 using any conventional method, includinguse of a thermally conductive paste. Given the electrically insulatingcharacter of a preferred submount, traces 19 and wirebonds 18 may beprovided to establish electrically conductive paths to and from thesolid state emitters 12A-12D.

Electrostatic discharge protection (ESD) devices 13A-13D such as zenerdiodes (or, alternatively, ESD devices such as ceramic capacitors,transient voltage suppression (TVS) diodes, multilayer varistors, and/orSchottky diodes) are integral to the package 50, and arranged over thesubmount 14 to protect the solid state emitters 12A-12D from harmfulelectrostatic discharge. In the illustrated embodiment, each solid stateemitter 12A-12D has an associated ESD device 13A-13D. In anotherembodiment (e.g. if multiple emitters 12A-12D should be connected inseries), each separately addressable path or separate conductive pathassociated with (e.g., in and/or on) the device 50 includes anassociated ESD device 13A-13D. Each ESD device 13A-13D may be surfacemounted on the submount 14.

A thermally conductive heatsink (e.g., metal or other conductive slug)is preferably provided below and in thermal communication with thesubmount 14 (e.g. via the leadframe 11) to conduct heat away from thesolid state emitters 12A-12D to a bottom side of the package 50. Theheatsink is preferably electrically inactive, and may be rendered sothrough use of an electrically insulating submount. The heatsink may beintegrally formed with the leadframe (e.g., as a portion of theleadframe of a thicker gauge or otherwise enhanced mass and/orthickness), or a heatsink may be placed proximate to the leadframe,according to any suitable manufacturing process. If a submount isprovided, the heatsink is preferably longer and/or wider than thesubmount to enhance lateral dispersion of heat emanating from the solidstate emitters.

In one embodiment, the submount 14 may be eliminated, with the emitters12A-12B (and optional ESD devices 13A-13D) being mounted on or over aleadframe 11. The leadframe may or may not be electrically active. Ifdesired to electrically isolate part or all of the leadframe, anelectrically insulating material (e.g., thin film or selectivelypatterned area) may be arranged between the leadframe and the emitters,with electrical traces and/or wirebonds included to provide electricalconnection to the emitters and/or ESD devices. 13A-13D. Alternatively,or additionally, an electrically insulating material may be disposedbetween at least a portion of the leadframe and an underlying heatsinkor slug to promote electrical isolation of the heatsink or slug. Inanother embodiment, solid state emitters (with optional ESD devices) maybe mounted on or over a heatsink or slug. The heatsink or slug may beelectrically active and used as a bottom side contact for devicesmounted thereon, with an electrically insulating material optionallybeing arranged below the heatsink or slug. Alternatively, oradditionally, an electrically insulating material may be disposed orselectively patterned between the heatsink or slug and the emittersarranged thereon.

In one embodiment, the emitters 12A-12D include a principally red LED12D, a first principally blue LED 12B lacking a phosphor (or otherlumiphoric material), a second principally blue LED 12C, and a thirdprincipally blue LED 12A having an associated yellow (or other)phosphor—with the blue LED 12A/yellow phosphor combination arranged toemit white light. Each solid state emitter 12A-12D is independentlycontrollable via different pairs of the leads 15A-16A, 15B-16B, 15C-16C,15D-16D. The package 50 may therefore be operated with any one, two,three, or four LEDs 12A-12D.

Although the emitters 12A-12D have been described herewith as embodyinga specific combination of solid state emitters and a lumiphor, it is tobe appreciated that any desired numbers and colors of solid stateemitters and lumiphors as disclosed herein may be employed.

FIGS. 2A-2D depict an emitter device package 50′ substantially similarto the package 50 illustrated and described in connection with FIG. 1.The package 50′ includes four solid state emitters 12A′-12D′ arrangedover a common submount 14′ and a common leadframe 11′. The package 50′includes a molded package body 10′ surrounding the submount 14′ and alens 20′ mounted over a central region of the package 50′, optionallyincluding an encapsulant material with scattering material serving as ascattering element 29′ arranged under the lens 20′. Conductive traces19′ provided on or over the submount 14′, and wirebonds 18′, provideelectrically conductive paths between the solid state emitters 12A′-12D′and electrical leads 15A′-15D′ and 16A′-16D′ extending from sides of thepackage body 10′. The leads 15A′-15D′, 16A′-16D′ may be arranged suchthat leads of opposite polarity type (e.g. anodes or cathodes) areprovided on opposite sides of the package body 10′. Registrationfeatures or molding depressions 8A′-8D′ may be formed adjacent tocorners of the package body 10′. A peripheral reflector 21′ may beprovided below the lens 20′. A thermally conductive heatsink or slug 17′(optionally integrated and/or integrally formed with the leadframe 11′)is exposed along a back side of the package 50′ and is in thermalcommunication with the submount 14′ to conduct heat away from the solidstate emitters 12A′-12D′. The heatsink or slug 17′ preferably has anexposed surface area that is larger than a facial area of the submount14′.

Construction details for, and features of, packages including multiplesolid state emitters are disclosed in the following U.S. patents andpublished patent applications: U.S. Patent Application Publication No.2008/0121921 to Loh, et al.; U.S. Patent Application Publication No.2008/0012036 to Loh, et al.; U.S. Patent Application Publication No.2007/0253209 to Loh, et al.; and U.S. Pat. No. 7,456,499 to Loh, et al.Solid state emitter packages as described herein may be combined withany one or more features of the foregoing U.S. patent and U.S. patentapplication publications to Loh et al., including, but not limited to:dual thickness leadframe construction; general electrical tracepatterns; and materials and methods of fabrication of variouscomponents.

In one embodiment, a solid state emitter package (e.g., packages 50,50′) such as described above includes multiple lumiphors in addition tomultiple solid state emitters. For example, with comparison to theembodiment of FIG. 1, at least two different LEDs 12A-12D may be coatedwith different lumiphors (e.g., phosphors). Alternatively, multiplelumiphors arranged to interact with emitters of different colors may becombined, and such combination may be coated (e.g., conformally coated)or otherwise disposed over at least two, at least three, or at leastfour solid state emitters 12A-12D. For example, multiple lumiphors maybe combined with an encapsulant and/or coated on or integrated with alens, with the multiple phosphors being arranged to interact with onesolid state emitter, two solid state emitters, or three or more solidstate emitters. Various combinations of multiple lumiphors and multiplesolid state emitters are described, for example, in U.S. PatentApplication Publication No. 2006/0152140 to Brandes, and U.S. PatentApplication Publication No. 2007/0223219 to Medendorp, et al., which areincorporated by reference herein. By appropriate selection of LED diecomponents and phosphor species, a close approach to the colortemperature of interest can be achieved in the light output of the lightemission device. Sizes (e.g., emissive area or frontal area) and/ornumbers of individual emitters disposed within a multi-emitter packagemay be varied to at least partially compensate for performancedifferences among emitters of different colors, as described in U.S.Patent Application Publication No. 2006/0152140 to Brandes.

In one embodiment, a solid state emitter package includes a plurality ofsolid state emitters, a plurality of conductive leads in electricalcommunication with the plurality of solid state emitters, and at leasttwo spatially separated conductive leads in electrical communicationwith at least one electrically conductive path associated with the solidstate emitter package, wherein the at least one electrically conductivepath is not in electrical communication with any solid state emitter ofthe solid state emitter package. The at least one electricallyconductive path may be susceptible to inclusion of a jumper, orinclusion of a control element.

FIG. 3 illustrates a simplified portion 111 of a multi-emitter packageincluding three solid state emitters 112A-112C. Such layout is similarto the layout illustrated in FIG. 2B, but with the omission of a fourthemitter. Electrical leads 115A-115D and 116A-116D extend laterallyoutward relative to a central region of the package. A submount 114includes electrically conductive traces or pads 119A, 119B, 120B, 119C,120C, 119D, 120D, with the submount 114 being used to support theemitters 112A-112C. Each emitter 112A-112C has two associated wirebonds118 to close an electrical path inclusive of the emitter 112A-112C andassociated traces or pads 119A, 119B, 120B, 119C, 120C. Electricallyconductive traces 119D, 120D have associated pins 121, 122 arranged incombination to receive an electrically conductive jumper (not shown)adapted to close an electrically conductive path therebetween. Such ajumper and pins 121, 122, together with conductive traces 119D, 120D,wirebonds 118D1, 118D₂, and contacts 115D, 116D provide an electricallyconductive path associated with the package that is not in electricalcommunication with any of the solid state emitters 112A-112C.Alternatively, the pins 121, 122 may be replaced with conventional(e.g., soldered) contacts coupleable to a control element (not shown).Such a control element may include, for example, any of a sensor, aswitch, a relay, a transistor, a current regulating element, and avoltage regulating element. Further details regarding utilization ofcontrol elements with a multi-emitter package such as described inconnection with FIG. 3 are discussed below in connection with FIGS. 4-5.Referring back to FIG. 3, contacts 115D, 116D are spatially segregatedfrom one another, as such contacts are arranged along different (i.e.,opposing) sides of a multi-emitter package. If desired, multipleelectrically conductive paths similar to the path involving pins 121,122 may be provided in a single multi-emitter package.

In one embodiment, the at least one electrically conductive pathassociated with the solid state emitter package (e.g., includingmultiple solid state emitter) comprises a jumper. Such a jumper may beremovably coupled to the solid state emitter package (e.g., via at pinsthereof) by a manufacturer or user of the solid state emitter package.Such a jumper may be used to provide interconnections on a personalcomputer board or other circuit board. This jumper may allow for lesscomplex circuit board layouts and may avoid the need for multi-layercircuit boards (or enable reduction of the number of layers thereof).Multi-layer circuit boards may be expensive, particularly when metalcore boards are required. Additionally, using multi-layer metal coreboards may reduce the ability to extract heat from an emitter package,as multiple interconnect layers may decrease thermal coupling of a metalcircuit board core to the package by increasing the thermal resistanceof the interconnection layers. In one embodiment, at least onemulti-emitter solid state emitter package including at least twoelectrically conductive leads in electrical communication with at leastone electrically conductive path associated with the solid state emitterpackage, wherein the at least one electrically conductive path not inelectrically conductive communication with any solid state emitter ofthe solid state emitter package. An electrically conductive pathassociated with a solid state emitter package may include a pathdisposed in and/or on the solid state emitter package. At least twoelectrically conductive leads in electrical communication (e.g., withone another, such as by way of one or more conductive elements disposedin and/or on a solid state emitter package) are preferably spatiallyseparated from one another, with such spatial separation includingplacement of the conductive leads on different (e.g., adjacent, oropposing) sides of the solid state emitter package. The solid stateemitter package is electrically (and preferably also thermally) coupledto a first side of a circuit board lacking a conductive (e.g., metal)core. In one embodiment, multiple emitter packages as previouslydescribed are coupled to a common circuit board of such type.

In one embodiment, at least one electrically conductive path associatedwith a multi-emitter solid state emitter package is coupled to at leastone control element. Multiple control elements of similar or differenttypes may be provided, such as in parallel or in series with oneanother, whether associated with a single electrically conductive pathor multiple electrically conductive paths associated with the solidstate emitter package. Examples of suitable control elements include,without limitation, sensors, switches, transistors, current regulatingelements, and voltage regulating elements. Such control element(s) maybe used to control or affect operation of one or more electricallyoperable elements spatially separated from the solid state emitterpackage containing the at least one conductive path, or alternativelythe control element may be used to control or affect operation of one ormore emitters within the solid state emitter package. One or moreemitters may therefore be operated responsive to a signal derived fromthe control element(s).

Referring to FIG. 4, at least a portion of a lighting system 200includes a solid state emitter package 250 (embodying a layoutsubstantially as illustrated in FIG. 3) in electrical communication withone or more electrically operable elements 241, 242 that are distinctfrom (e.g., spatially separated from) the emitter package 250.Electrical leads 215A-215D and 216A-216D extend laterally outward onopposing sides relative to a central region of the package 250. Threepairs of leads 215A-216A, 215B-216B, 215C-216C are in electricalcommunication with three emitters (not shown), respectively, of thepackage 250. Electrical leads 219D, 220D extend from another side of thepackage 250 and are in conductive communication with the remaining leads215D, 216D, respectively. Intervening conductive elements such aswirebonds may be used to facilitate electrically conductivecommunication between leads 215D, 219D and leads 220D, 216D. A controlelement 230 is disposed in electrical communication with the leads 219D,220D, with the control element 230 and leads 215D, 216D, 219D, 220D,forming an electrically conductive path associated with (e.g., in and/oron) the package 250 that is independent of any solid state emitter ofthe package 250. One or more control elements 230 may be spatiallyseparated from the package 250, which may be advantageous, for example,to permit remote sensing and/or control. One or more electricallyoperable elements 241, 242, which may be spatially separated from andexternal to the package 250, may be disposed in electrical communicationwith the leads 215D, 216D. Since the electrically operable elements 241,242 are ultimately arranged in electrical communication with the controlelement 250, the control element 230 may be arranged to control and/oraffect operation of such elements 241, 242. The electrically operableelements 241, 242 may include supplemental emitters, cooling elements(e.g., fans, heatpipes, etc.), user-perceptible alarm or indicationelements (e.g. arranged to output visible, audible, tactile, or similaralarms or indications), user-perceptible display elements, and similaritems. The control element 230 may receive a control input 229, such asmay be provided by a manual switch, external processor, or otherexternal signal generating means. In one embodiment, the control element230 includes a wireless receiver and the control input 229 may becommunicated wirelessly to the control element 230.

In various embodiments, the control element 250 may comprise one or moreof any of the following: a sensor, a switch, a transistor, a currentregulating element, and a voltage regulating element. In certainembodiments, the control element 230 may comprise at least one sensorarranged to sense light—such as presence, absence, color and/orintensity of any of incident light and light generated by one or moreemitters of the package 250—and responsively affect operation of theelectrically operable elements 241, 242. For example, the electricallyoperable elements 241, 242 may comprise one or more emitters that may beoperated according to need for supplemental lighting (e.g., with respectto color and/or intensity) as determined by ambient light conditionsand/or emissions generated by one or more emitters of the package 250.In certain embodiments, the control element 230 may include a motionsensor, an accelerometer, a temperature sensor, a pressure sensor, amoisture sensor, a chemical sensor, a strain gauge, a current sensor, ora voltage sensor.

Referring to FIG. 5, at least a portion of a lighting system 300includes a solid state emitter package 350 (or primary emitter package350), embodying a layout substantially as illustrated in FIG. 3, inelectrically conductive communication with at least one control element330 capable of affecting operation of the emitter package 350 and/or oneor more external devices (such as a secondary emitter package 450). Theat least one control element 330 may include one or more secondaryelectrically conductive paths arranged to control or affect operation ofthe emitter packages 350, 450, with the secondary electricallyconductive paths not being in electrically conductive communication witha primary conductive path of the emitter package 350 including leads315D, 319D, 320D, 316D.

Electrical leads 315A-315D and 316A-316D extend laterally outward onopposing sides relative to a central region of the primary emitterpackage 350. Three pairs of leads 315A-316A, 315B-316B, 315C-316C are inelectrical communication with three emitters (not shown), respectively,of the primary package 350. Electrical leads 319D, 320D extend fromanother side of the package 350 and are in electrically conductivecommunication with the remaining leads 315D, 316D, respectively. Thecontrol element 330 (more specifically, a portion 331 thereof) isdisposed in electrical communication with the leads 319D, 320D, with thecontrol element 330 and leads 315D, 316D, 319D, 320D, forming aconductive path associated with the package 350 that is independent ofany emitter of the package 350. In one embodiment, the control element330 may comprise one or more transistors, relays, or other electricallyoperable switching and/or regulating devices 332, 334, with the portion331 comprising one or more sensors arranged to generate one or moresensor output signals, with operation of the switching and/or regulatingdevices 332, 334 being responsive to the one or more sensor outputsignals. Additional switching and/or regulating elements 335A, 335B,335C may be associated with leads 315A, 315B, 315C associated with thethree emitters (not shown) of the primary solid state emitter device350. A processing element 328 may also be in electrical communicationwith the control element 330 to affect operation thereof.

At least one first switching and/or regulating device 332 may be inelectrical communication with at least one solid state emitter of theprimary solid state emitter package 350. At least one second switchingand/or regulating device 334 may be in electrical communication with atleast one electrically operative device that is distinct from theprimary emitter package 350, such as a secondary solid state emitterpackage 450 (or at least one control element 435 associated with thesecondary package 450) optionally containing four solid state emitters(not shown). As illustrated in FIG. 5, a secondary solid state emitterpackage 450 may include four lead pairs 415A-416A, 415B-416B, 415C-416C,415D-416D each having an associated input conductor 410A-410D andproviding electrical communication with a different solid state emitter(e.g., as shown in FIG. 2B) of the secondary solid state emitter package450. A first electrically conductive path including the portion 331 ofthe control element 330 is independent of one or more additionalelectrically conductive paths including the switching and/or regulatingdevices 332, 334. For example, the portion 331 may comprise a sensor, arelay, a transistor, or similar element, including a primaryelectrically conductive path through a primary segment thereof, and asecondary electrically conductive path through a secondary segmentthereof, with the primary and secondary electrically conductive pathsnot being conductively coupled to one another.

In operation of the system 300, input conductors 310A-310D supply powerto the input leads 315A-315D of the primary emitter package 350. Thefirst three leads 315A-315C power three solid state emitters (not shown)of the primary emitter package 350. The fourth lead 315D and associatedside lead 319 supply power to a control element 330 (or a portion 331thereof). Based on conditions sensed by or otherwise dictated to theinput portion 331 (e.g., as sensed by a sensor, dictated by an externalinput, or dictated by the processor 328), the switching and/orregulating devices 332, 334 of the control element 330, in associationwith the switching and/or regulating elements 335A-335C, 435 associatedwith the primary and secondary emitter packages, respectively, maycontrol or affect operation one or more emitters of the primary and/orsecondary emitter packages 350, 450. In one situation, operation of atleast a portion of the primary emitter package 350 may be curtailed orstopped, while operation of at least a portion of the secondary emitterpackage 450 is increased or initiated (or vice versa). The primary andsecondary emitter packages 350, 450 may be operated in tandem, incomplementary fashion, or opposite fashion relative to one another toachieve desired light color, intensity, and/or reliability. Automaticswitching between packages 350, 450 may be effected based uponattainment of specified conditions (e.g., excess temperature,malfunction/failure, insufficient or undesired emission color and/orintensity). Additional emitters and/or emitter packages may be disposedin series or parallel, and operated in tandem and/or cascading fashionas desired. A large quantity of emitters and/or emitter packages asdescribed herein may be disposed in an array and operated according toany suitable operating mode as disclosed herein to achieve a desiredresult.

Devices according to the present invention may be used as described inU.S. Pat. No. 7,213,940, which is hereby incorporated by reference as ifset forth fully herein. A combination of light exiting a solid stateemitter package as disclosed herein, may, in an absence of anyadditional light, produce a sub-mixture of light having x, y colorcoordinates within an area on a 1931 CIE Chromaticity Diagram defined bypoints having coordinates (0.32, 0.40), (0.36, 0.48), (0.43, 0.45),(0.42, 0.42), (0.36, 0.38).

As indicated previously, one aspect of the invention relates to a solidstate emitter package including: a plurality of solid state emitters; aplurality of conductive leads in electrical communication with theplurality of solid state emitters; and at least two spatially separatedconductive leads in electrical communication with at least oneelectrically conductive path associated with the solid state emitterpackage, wherein the at least one electrically conductive path is not inelectrically conductive communication with any solid state emitter ofthe solid state emitter package. In one embodiment, current isindependently controllable to each solid state emitter of the pluralityof solid state emitters using the plurality of conductive leads. In oneembodiment, the plurality of solid state emitters comprises non-whitesolid state emitters. In one embodiment, each solid state emitter of theplurality of solid state emitters is arranged with lateral edge spacingof less than about 1.0 mm from at least one adjacent solid state emitterof the plurality of solid state emitters. In one embodiment, theplurality of solid state emitters comprises at least two solid stateemitters having peak emissions of wavelengths at least about 50 nmapart. In one embodiment, the at least one electrically conductive pathassociated with the solid state emitter package comprises a jumper. Inone embodiment, the at least two spatially separated conductive leadsare disposed on different sides of the solid state emitter package. Inone embodiment, the at least one electrically conductive path associatedwith the solid state emitter package comprises at least one controlelement. In one embodiment, the at least one control element is adaptedto control or affect operation of at least one solid state emitter ofthe plurality of solid state emitters. In one embodiment, the at leastone control element is adapted to control or affect operation of atleast one electrically operated element that is spatially separated fromthe solid state emitter package. In one embodiment, the at least onecontrol element comprises any of a sensor, a switch, a transistor, acurrent regulating element, and a voltage regulating element. In oneembodiment, the plurality of solid state emitters includes at least oneprincipally red solid state emitter having peak emissions within awavelength range of from 590 nm to 680 nm, and at least one principallyblue solid state emitter having peak emissions within a wavelength rangeof from 400 nm to 480 nm, wherein the solid state emitter package isdevoid of any principally green solid state emitter having peakemissions within a wavelength range of between 510 nm and 575 nm. In oneembodiment, a light emitting device includes a solid state emitterpackage as described hereinabove, and at least one solid state emitterthat is spatially separated from the solid state emitter package andthat is operatively coupled to the at least one electrically conductivepath associated with the solid state emitter package.

As indicated previously, another aspect of the invention relates to asolid state emitter package including a plurality of solid stateemitters, a plurality of first conductive leads in electricalcommunication with the plurality of solid state emitters; and at leasttwo second conductive leads in electrical communication and disposed ondifferent sides of the solid state emitter package, wherein the at leasttwo second conductive leads are not in electrically conductivecommunication with any solid state emitter of the plurality of solidstate emitters. In one embodiment, the at least one second conductiveleads are in electrical communication with at least one control element.In one embodiment, the at least one control element is adapted tocontrol or affect operation of at least one solid state emitter of theplurality of solid state emitters. In one embodiment, the at least onecontrol element is adapted to control or affect operation of at leastone electrically operated element that is spatially separated from thesolid state emitter package. In one embodiment, the at least one controlelement comprises any of a sensor, a switch, a transistor, a currentregulating element, and a voltage regulating element. In one embodiment,the plurality of solid state emitters includes at least one principallyred solid state emitter having peak emissions within a wavelength rangeof from 590 nm to 680 nm, and at least one principally blue solid stateemitter having peak emissions within a wavelength range of from 400 nmto 480 nm, wherein the solid state emitter package is devoid of anyprincipally green solid state emitter having peak emissions within awavelength range of between 510 nm and 575 nm. In one embodiment, alight emitting device includes a solid state emitter package asdescribed hereinabove, and at least one solid state emitter that isspatially separated from the solid state emitter package and that is inelectrical communication with the at least two second conductive leads.

One embodiment includes a lamp including at least one solid stateemitter package as disposed herein. Another embodiment includes a lightfixture including at least one solid state emitter package as disclosedherein. In one embodiment, a light fixture includes a plurality of solidstate emitter packages. In one embodiment, multiple solid state emitterpackages as disclosed herein may be operatively connected (e.g., inparallel or in series) and/or integrated in a single lamp or fixture. Inone embodiment, multiple solid state emitter packages as disclosedherein may be operatively coupled to a common current adjuster. Inanother embodiment, each solid state emitter package may have adedicated current adjuster. In one embodiment, a light fixture isarranged for recessed mounting in ceiling, wall, or other surface. Inanother embodiment, a light fixture is arranged for track mounting.

In one embodiment, an emitter package as disclosed herein, lampincorporating at least one such emitter package, or light fixtureincorporating at least one such emitter package, is adapted to promoteplant growth by emitting an electromagnetic spectrum appropriate forphotosynthesis.

In one embodiment, an enclosure comprises an enclosed space and at leastone solid state emitter package as disclosed herein, wherein upon supplyof current to a power line, the at least one emitter package illuminatesat least one portion of the enclosed space. In another embodiment, astructure comprises a surface or object and at least one emitter packageas disclosed herein, wherein upon supply of current to a power line, theemitter package illuminates at least one portion of the surface orobject. In another embodiment, an emitter package as disclosed hereinmay be used to illuminate an area comprising at least one of thefollowing: a plant, a greenhouse, a swimming pool, a room, a warehouse,an indicator, a road, a vehicle, a road sign, a billboard, a ship, atoy, an electronic device, a household or industrial appliance, a boat,and aircraft, a stadium, a tree, a window, a yard, and a lamppost.

The foregoing disclosure thus discloses various multi-emitter packageseach including multiple LEDs, with features to enhance light outputquality, efficiency, and/or controllability, and devices incorporatingsuch packages

While the invention has been has been described herein in reference tospecific aspects, features and illustrative embodiments of theinvention, it will be appreciated that the utility of the invention isnot thus limited, but rather extends to and encompasses numerous othervariations, modifications and alternative embodiments, as will suggestthemselves to those of ordinary skill in the field of the presentinvention, based on the disclosure herein. Any of various elements orfeatures recited herein is contemplated for use with other features orelements disclosed herein, unless specified to the contrary.Correspondingly, the invention as hereinafter claimed is intended to bebroadly construed and interpreted, as including all such variations,modifications and alternative embodiments, within its spirit and scope.

1. A solid state emitter package comprising: a plurality of electricallyactivated solid state emitters including at least one principally redsolid state emitter having peak emissions within a wavelength range offrom 590 nm to 680 nm, at least one principally blue solid state emitterhaving peak emissions within a wavelength range of from 400 nm to 480nm, and at least one supplemental electrically activated solid stateemitter having peak emissions within a wavelength range of from above575 nm to 590 nm, wherein the solid state emitter package is devoid ofany principally green solid state emitter having peak emissions within awavelength range of between 510 nm and 575 nm; and at least one of thefollowing elements (a) to (c): (a) a common leadframe including aplurality of conductive leads arranged to supply current to theplurality of solid state emitters; (b) a common substrate arranged tostructurally support the plurality of solid state emitters; and (c) acommon reflector arranged to reflect light emissions of each solid stateemitter of the plurality of solid state emitters.
 2. The solid stateemitter package of claim 1, wherein current is independentlycontrollable to the at least one principally red solid state emitter andthe at least one principally blue solid state emitter.
 3. The solidstate emitter package of claim 1, further comprising a lumiphoricmaterial that is arranged to convert at least a portion of emissionsfrom any of the at least one principally red solid state emitter and theat least one principally blue solid state emitter, wherein thelumiphoric material generates emissions having a peak wavelength that isdifferent from a peak wavelength of each of the at least one principallyred and the at least one principally blue solid state emitter.
 4. Thesolid state emitter package of claim 3, wherein the lumiphoric materialis spatially separated from any of the at least one principally redsolid state emitter and the at least one principally blue solid stateemitter.
 5. The solid state emitter package of claim 1, being devoid ofany lumiphoric material that is arranged to convert emissions from atleast one principally red or at least one principally blue solid stateemitter of the plurality of solid state emitters.
 6. The solid stateemitter package of claim 1, being devoid of any additional solid stateemitter.
 7. The solid state emitter package of claim 1, characterized byany of the following: the at least one principally red solid stateemitter comprises a plurality of principally red solid state emitters;and the at least one principally blue solid state emitter comprises aplurality of principally blue solid state emitters.
 8. The solid stateemitter package of claim 1, characterized by any of the following: theat least one principally red solid state emitter comprises a pluralityof principally red solid state emitters, including at least twoprincipally red solid state emitters having peak emissions of differentwavelengths; and the at least one principally blue solid state emittercomprises a plurality of principally blue solid state emitters,including at least two principally blue solid state emitters having peakemissions of different wavelengths.
 9. The solid state emitter packageof claim 1, comprising at least two of elements (a), (b), and (c). 10.The solid state emitter package of claim 1, further comprising at leastone of a mixing element and a scattering element arranged to promotemixing between emissions of the at least one principally red solid stateemitter and the at least one principally blue solid state emitter. 11.The solid state emitter package of claim 1, wherein each solid stateemitter of the plurality of solid state emitters is arranged withlateral edge spacing of less than about 1.0 mm from at least oneadjacent solid state emitter of the plurality of solid state emitters.12. The solid state emitter package of claim 1, further comprising: aplurality of conductive leads in electrical communication with theplurality of solid state emitters; and at least two spatially separatedconductive leads in electrical communication with one another to provideat least one electrically conductive path through the solid stateemitter package that is not in electrical communication with any solidstate emitter of the solid state emitter package.
 13. A lamp or lightfixture comprising at least one solid state emitter package according toclaim
 1. 14. The lamp or light fixture of claim 13, being adapted topromote plant growth by emitting an electromagnetic spectrum appropriatefor photosynthesis.
 15. A method for promoting plant growth, the methodcomprising illuminating at least a portion of a plant with the lamp orlight fixture of claim
 14. 16. The solid state emitter package of claim1, further comprising at least one additional supplemental solid stateemitter having peak emissions within a wavelength range of from 480 nmto below 510 nm.
 17. The solid state emitter package of claim 1, whereincurrent is independently controllable to the at least one principallyred solid state emitter, to the at least one principally blue solidstate emitter, and to the at least one supplemental solid state emitter.18. A solid state emitter package comprising: a plurality ofelectrically activated solid state emitters; a plurality of conductiveleads in electrical communication with the plurality of solid stateemitters; and at least two spatially separated conductive leads inelectrical communication with one another to provide at least oneelectrically conductive path through the solid state emitter packagethat is not in electrical communication with any solid state emitter ofthe solid state emitter package.
 19. The solid state emitter package ofclaim 18, comprising at least one of the following elements (a) to (c):(a) a common leadframe including a plurality of conductive leadsarranged to supply current to the plurality of solid state emitters; (b)a common substrate arranged to structurally support the plurality ofsolid state emitters; and (c) a common reflector arranged to reflectlight emissions of each solid state emitter of the plurality of solidstate emitters.
 20. The solid state emitter package of claim 18, whereinthe at least one electrically conductive path associated with the solidstate emitter package comprises at least one control element.